| bytes | Package bytes implements functions for the manipulation of byte slices. |
| crypto/cipher | Package cipher implements standard block cipher modes that can be wrapped around low-level block cipher implementations. |
| crypto/internal/boring | Package boring provides access to BoringCrypto implementation functions. |
| crypto/internal/impl | Package impl is a registry of alternative implementations of cryptographic primitives, to allow selecting them for testing. |
| crypto/subtle | Package subtle implements functions that are often useful in cryptographic code but require careful thought to use correctly. |
| encoding/json | Package json implements encoding and decoding of JSON as defined in RFC 7159. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| hash | Package hash provides interfaces for hash functions. |
| internal/asan | Package asan contains helper functions for manually instrumenting code for the address sanitizer. |
| internal/goos | package goos contains GOOS-specific constants. |
| internal/msan | Package msan contains helper functions for manually instrumenting code for the memory sanitizer. |
| internal/race | Package race contains helper functions for manually instrumenting code for the race detector. |
| internal/testenv | Package testenv provides information about what functionality is available in different testing environments run by the Go team. |
| io | Package io provides basic interfaces to I/O primitives. |
| math/rand | Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work. |
| os | Package os provides a platform-independent interface to operating system functionality. |
| runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| testing | Package testing provides support for automated testing of Go packages. |
| time | Package time provides functionality for measuring and displaying time. |